Synchro-Sette

SYNCHRO-SETTE

THE SUBCRIPTION MAGAZINE FOR THE SINCLAIR ZX-81 1 TS -1000

MICROCOMPUTERS

VOLUME 2 NUMBER 1

INSIDE THIS ISSUE JAN. 1983

LETTERS TO THE EDITOR 2

HISTORY-THE MARK 1 COMPUTER ... 6
NUMBER MUNCHER-GAME PROGRAM 7
THE COMPUTER TUTOR

SIMULATING PRINT USING ...8

1982 CASSETTE PROGRAM INDEX .... 12
1982 MAGAZINE ARTICLE INDEX. .... 13
JUMP SORT-VISUAL SORT PROGRAM. 14

EDITOR RAMB LINGS 15

HELP YOUR CHILD IN SCHOOL 19

SYCHRO - SETTE IS PUBLISHED MONTHLY BY s THE S & S COM PR NY
388 W. LUKE ST. flPPISOH 111. 60101 <312) 628-8933

Dear Ed,

Your "View of VtHCalc" in the
October issue was helpful to ny
understanding of this (Timex)
program, but as you may have
discovered by know, there was a
serious flaw in the example which
led to an erroneous conclusioon *
Your example called for formulae in
boxes B5 through G5 which required
data f ran box G4 . Bat G4 also
contains a formula rather than data
and since Vu-Calc ootputes by row
from left to right starting frcm row
A and then going down row by row,
the numeric data required for the
formulae in bates B5 through F5 will
not exist and an error report C/5110
results.

you pointed out, it would be very
inconvenient if it didn’t.

Yojt example can be restructured
to obey the Vu-Calc rules by simply
interchanging the rows and colunns.
Then it wnrks perfectly.

The program also has a simpler
way to mix relative and absolute
parts in a formula as discovered on
page 5 of the instructions. You
refix the parts that are to be
absolute with a <$> when typing in
the f orrnu la and then choose the
relative option as usual to make the
other parts relative. This saves
having to type in all the formulae
individually as you did in your
example.

This didn't happen with your
example, possibly because box G4
contained old data as a result of
the step by step way you built ip
the example, but it will happen when
you start with only the raw data.

The Vu-Calc instructions tell you
cn page 6 to be sure that data
required by the formula in a given
box, be oorputed before reaching
that box, i,e, in any row above the
box on the left of the box in the
same row.

There is one part of the
instructions, also on page 5, that I
don't understand. The statanent is
that "you may use up to 40 formulae
That seoned to me to be a
terrible liirutatation and to test
it, I put in about 50 formulae. They
all worked perfectly - so 1 don't
knew if this is a typo (400 allowed)
or refers to sanething I don't
understand .

Bo you have any informtion on
this?

This problon also led you to
conclude that Vu-Calc didn't corpute
the whojje table at once because seme
of your data didn't change when you
thought it should. That was
evidently because it was still
working with the old values. In fact
Vu-Calc does oaipute the whole table
at cnee as I verified by scattering
formulae all over the table and
observing the results change as I
changed the input data and then
executed the calculate mode, I'm
certainly glad it does, because as

Sincerely ,

Bob Keyser - Ehcinitas, CA

Read the letter frcm the following
subscriber - Ed,

Dear Ed,

There is a "glaring weakness" in
your review of Vu-Calc in the
October issue. On page 17 aider the
heading "Changing Data", paragraph 2

2

states the data in box 02 has not
changed. Hiat is because this colum
references box GO 4 Which has not yet
been calculated.

Page 6 of the instruction sheet
provided with the tape, clearly
warns against this error .
Calculations start at the hone
square and proceed horizontally
along row A, then down to row B,
etc.

You missed what I consider the
most glaring weakness of the
program. The instructions state "You
may use up to 40 formulae — " , This
apparently means you can press the
<F> key to enter a formula ^ to a
maximum of 40 times. After that, you
reach an unrecoverable error
condition that will not allow you to
enter any more formulae. Deleting
formulae in the boxes will not allcw
you to recover frcm this condition.
This happens without warning. If you
are using formulae to load data into
the boxes, this condition can be
reached very quickly.

Other than this , I generally
agree with your review (except that
the dash between the box
co-ordinates in the sample formula
is a minus signK I vrould like to
see more reviews in Synchro-Set te .

Yours Truly,

D.V. Carvilie
Sperry Uhivac PSD
New York

Thank you both for your ( insight
in proper use of Vu-Calc and
especially for clearing up the data
changing fonrat mistake.

Hr. Carvilie says that after the
40 th formula is entered, an
un recoverable error condition occurs
where no more formula can be entered
and deleting previously entered
formula does not help.

Mr. Keyser says that he has
entered 50 formulae and they all
worked perfectly. Does the 40
maximum refer to individually
entered formulae , replicated

formulae or both. Who is right?

In regard to Mr. Carvilie f s
ccntnent regarding the dash being a
minus sign in the Vu-Calc sample,
this to me was one of the most
"glaring weaknesses" in the Vu-Calc
documentation . The dash looks more
like a dot and there is no immediate
reference that this dash (dot) is to
be a logical operator to perform
subtraction. Also, the logical
operators for addition, subtraction,
multiplication and division should
have been shown and explained or at
least carmen ted an in the carmand
summary on page 8 of the
documentation .

Most people have no idea how many
of the subscribers had purchased
Vu-Calc and didn't know what to do
with it or how to use it until the
October article appeared. The most
eanmon complaint was the in -ability
to understand the documentation and
particularly how to enter formulae.
The second most cannon oanplaint was
how to duplicate or replicate
formulae.

For those of us who have had
experience with Visa-Calc type
programs on mare expensive
computers, Vu-Calc was pretty much
second nature and even redundant.
All I ask is that we don't make the
mistake of assuming the all the
readers have the same knowledge we
do and write things based cn this
assumption. I have made this mistake
more than once in other areas and
will probably make it again * I
encourage any chastisement that I
deserve from you readers (keep the
letters clean, though) - Ed,

D^r Fred (I think he meant Bi)

I received the Sinclair and
Mindware printers within a week of
each other and I like both. My
Sinclair printer also needs a prompt
to get the paper to feed (annoying
but liveable) and like you, I

haven’t tried to adjust it yet,

I an now sending for some paper
from;

3

E. Alvarez
PO BOJC 1025
Oviedo, FL, 32765

which is supposed bo have a
whiter background for better
contrast {graphics on Sinclair’s
printer leave a lot to be desired),

Mindware's printer is great. It’s
jiffit too bad it doesn't use wider
paper. The ribbon cartridge fran
Radio Shack is part # 26-3507, By
using packing label tape in the
Mfl-100 for mailing labels, you dcn't
even need to use glue - just lick
the back and stick on cn.

Your "FILE" OCT/02 program is
about the best I've seen. By
adding;

2375 IF Y$* rt C" THEM OOPY

and using the fW-100, it*s hard to
beat for mailing lists,

I picked op a Diskwasher
Competition Joystick and with small
wire and cue cut inside, it works
great on my ZX-81.

You mg is terrific - I just wish
they came faster. Keep op the good
work,

Jake Breil - Cypress, CA

Dear Jake ,

Thanks for the kind words and
information. The only problm I have
with the print-outs of both printers
is that they are extremely hard for
the printer to make good proofs
fran. The grey backgound of the
aloninized paper an the Sinclair
printer and the blue ink on the
cartridge of the W-10Q are awfully
hard for printing proof cameras to
pick op,

I find that I am not alone with
the problem of tiaving to pull the
paper on the Sinclair printer - a
few other people have written me
with the same situation.

I purchased the Radio Shack

cartridge which has black ink and it
printed out very light. It might
have been ai old ribbon that was
partially dried out.

Bob De Lisle of Hanmcnd Indiana
sent me seme sample cqpies made with
the CAI printer cn a white
background aluminized paper. The
graphics are superb and all
characters are easily read. The copy
is however, also very light. Whether
this is the same type of paper that
Alvarez sells, I don't know.

The Mfl-100 gives the most
readable copy I have seen to date -
Ed.

Dear Ed,

My main reason for writing is to
ask you bo put a LPRIWT option in
your future 'menus’ . Maybe there is
an easy way to do it but I haven't
stumbled on it yet - seme of us do
have printers, don't forget 1

I, for one would like to see more
business/home programs & fewer
games. Tte business /hone programs
are much more fun for me.

D.A, Potts H> - Independence, MO

Dear D.A. ,

When the programs that could use
print-out were written, most people
hadn't even seen a printer yet. We
intend bo use the print-cut
capability in future programs.

In the meantime, you are left
with 3 options to convert existing
programs to print. The first is for
listing programs which uses the
LLIST command of which you are
probably aware of already.

The second is to use the OOPY
command in a program line. Keep in
mind that this command will copy
whatever is cn the screen - even
blank spaces and lines. If you write
a routine such as:

1000 INPUT A$

1010 CLS

1020 PRINT A$

1030 COPY

the data you input for A$ will
appear at the top of the screen and
the printer will copy it to paper
along with all the blank lines below
it.

The third procedure, which is
probably the most useful, is to use
the LPRINT carmand . Ibis ccmnand
allows formatting of the print-out
to paper . A sample program to
demonstrate this would be:

10 SCROLL

20 PRINT "ENTER NAME?"

30 INPUT N$

40 SCROLL

50 PRINT "ENTER TAB?"

60 INPUT T
70 SCROLL
80 LPRINT TAB T;N$

90 GOTO 10

Play around with this program and
try bp become familiar with how the
print-out can be formatted anywhere
on the paper. In almost all

programs, it would only require the
entry of lines using a format like
line 80 uses in this program.

One aid thing I’ve noticed is
that if the last data printed on the
screen is at the batton-most

available line position, U^RINT

woVt work. The computer treats it
as a PRINT command and gives a
screen full error even though
nothing extra is added to the
screen. Delete line 70 fran the
sample and you can observe this

As far as bus i ness /hane vs. games
programs, I f m sure if I changed the
ratio, I would here complaints fran
the other end. We will continue to
try to have sane of -^ach - Ed.

Dear Ed,

Will use of a mini-drive for the
TS-1Q00 allow cne to input data
independently of the program? More
importantly, do you foresee any
possibility of being able to utilize

gne set of data in more than one
program by being able to access that
data fran an independent source
( another tape recorder or disk
drive) or will cne be forever
destined bo duplicate the data each
time it is needed for additional
programs .

Also, is there any way that you
know of where two programs can be
chained together so that a canman
set of data can be used assuming
that it is not possible to introduce
data independently of a program?

Let me just say that this
beginner is ever and eternally
grateful to you and all those
involved in reaching out to us in
such a friendly, scholarly,
enthusiastic and helpful way.
Although most of us will always be
c Ignoring for "more, more, more! 11 —
we will all be quite satisfied and
grateful for whatever bounties we
receive,

Beatrice Spencer

St. Thonas, Virgin Islands

Dear Bea,

I an sorry that I couldn't print
your whole letter with all of the
questions but in regard to
separating data fran a program,

Ttere is a utility program that
allows data to be stored cn tape
separate fran the program. It uses
only 500 bytes of memory and can be
used cn a 2K machine. It sells for
17,00 (1.50 postage & handling - CA
res. add 6% or 6.5% sales tax) and
is available fran:

Coe monies

PO BOX 10358

San Jose, CA, 95157

Otherwise, separate disk drives
or recorders won’t solve your
problem.

As far as chaining prog rains are
concerned, I’m sure it is possible
and would require another utility
program which I have seen for other

*3

cent, cn page 18

Machines that are partly
mechanical and partly electrical are
"electromechanical". The invention
of the ASCC t Automatic Sequence
Controlled Calculator) or "Mark 1"
was a milestone in electromechanical
calculation. It was the joint
project of Howard Aiken, professor
of applied mathmatics at Harvard,
and Thomas J* Watson, president of
IBM.

Watson was not a designer of
machines - he was a salesman and
executive - but he had the insight
to see the value of Aiken's ideas
and to do for him what the
chancellor or exchequer was not
willing to do for Babbage -
underwrite his invention so that it
could become a reality.

Aiken wanted to build a general
purpose computer that could handle
not only his own special
mathematical problems but any kind
of problem. Watson bought Aiken's
ideas and in 1941, let him write his
own ticket and gave his four top IBM
engineers as helpers on the
project .

The work took five years and in
1944 the Mark I was formally
presented to Harvard University by
Watson. It was Babbage's dream come
true.

The new machine consisted largely
of standard Hollerith counters with
a superimposed and specially
designed automatic tape sequence
control for directing the operations
of the machine. The Mark 1 was an
electromechanical device 51 feet
long and 8 feet high; it had more
than 760,000 parts and included 500
miles of wire. This machine weighed
5 tons.

It could carry out any specified
sequence of five fundamental
operations - Edition, subtraction,
multiplication , division and
reference to tables of results
already confuted. The input was in
the form of punched cards and switch
positions. The output was punched
into cards or printed by electric
typewriters .

Although archaic and bulky by
today's standards, one has to admire
the ingenuity of the device because
there were none of the ccnpcnents
used in today's machines such as
microprocessors, transistors or even
vacuum tubes . The calculating
process was done entirely by relays
similiar to those used in
temperature thermostat controls or
automobile applications of today*

Needless to say, the process was
slow and consumed enormous amounts
of electrical energy. The Mark 1 was
also very noisy and was said to
sound like "a bunch of women, all
pounding a*ay at typewriters at the
same time" because of the clicking
of all the relays.

Despite these drawbacks, the Mark
1, as originally built, could make
limited decisions by making
comparisons. In 1943, While the
first general -purpose
electromechanical computer, the Mark
1 was being built, work was being
started cn the ENIAC, the first
electronic computer because it used
vacuum tubes. This proved to be the
death knell for the elec tamechan leal
concept and insured the short life
and obsolescence of the Mark 1 and
computers of this type.

The Mark 1 had a successor, the
Mark 2, which was constructed by the
Harvard laboratory tnder Aiken's

cont, on page 18

An excellent and addicting game.
Tot inverse numbers between 0 and 9
will appear on the screen at a time.
The "rancher " will then proceed fran
the left to the right of the screen.
His direction can be controlled by
pressing the < 1 > key to make him
move 14 ) and the < 0 > key to make him
move down.

The muncher will make ten passes
and after each pass, the new score
will be displayed in the center of
the screen. Tty to get the highest
numbers for the highest score.

If the imncher tries to eat the
score, the game will be over and a
whole bunch of points will be
deducted fran your score.

This gane contains a sreen
manory -mapping routine that is
controlled fran lines 40 to 255.

1 FAST

2 POKE 16418,0

3 FOR t**l TO 768

4 PRINT CHR$ 8 ;

5 NEXT N

6 LET 0255

7 SUM

40 1ST P=(PEEK 16396) +256* (PEE
K 16397)

50 LET S*0

60 LET R=P+133
70 FDR T»1 TO 10
80 FOR Z=1 TO 8
90 LET X=RND*768+P
93 IF X<( (Rt©*400)+P) THEN GOT
O 90

96 IF X> ( { RND * 668 ) +P ) THEN GOT
0 90

100 IF PEH< X=118 THEN GOTO 90
110 POKE X, 1S6+WT (10+IWD)

120 NEXT Z
130 EOR Z=1 TO 31
140 IF PEEK <R+Z> <> 8 THEN LET S
=S+PEQC (R+Z) -156
145 IF PEEK (R+Z) =0 THEN GOTO 2
40

150 POKE R+Z, 18

155 POKE R+Z-1,22

160 POKE R+Z , 8

165 POKE R+Z-1,8

170 IF INKEY$="0* THEN LET R=R+

33

180 IF R>=768+P THEN LET R=R-33
190 IF INKEY$="1" THEN LET R*R-
33

200 IF R<-P THEN LET R=R+33
210 NEXT Z

220 PRINT AT 12,15;S
225 LET OCCDE SI R$ S
230 NEXT T
240 CIS

250 PRINT AT 12,6;"YOUR SCORE IS
")S

260 PAUSE 200
270 CIS
280 RUN

*

T

*

tAe ^<mvfiuteh ^Fido'i

Hello Class! Welcome to the new
year. Is everybody ready to resume
classwork? Good!

Today’s subject will be
formtting numbers. All of you, I m
sure, have seen printouts of data
where numbers were neatly printed in
col urns and the decimal points all
lined up and all the trailing zeroes
were added after the decimal point.

Has anyone any idea how this is
done? The man in the back has his
hand up - yes sir?

The gentleman says that he is not
sure how it is done on the Sinclair
Computers but on the Radio Shack
Computers, a carmand called PRINT
USING is used.

If one were to RUN this program
on the IRS -80 and OTTER the
following values for each input, the
values in the right column would be
observed:

VALUE PRINT USING VALUE

1

12*7

.005

15796.3

98765432*1

1.00

12*70

.01

15,796*30

*98,765,400.00

As you can see, this oanmand
easily rounds off any number up to
999999.99 to 2 decimal places. It
ignores any numbers more than six
digits to the left of the decimal
point and more than 2 digits to the
right of the decimal point*

I am glad he brought this op.
PRINT USING is a powerful carmand
that allows the user automatic
formatting of numbers . A sample
program on the IRS-80 would be as
follows:

10 LET A$ ="!## ,###.##"

20 INPUT B
30 PRINT USING A$:B
40 QUID 20

So as you can see, it is a wry
powerful carmand. This is, however
mly half of what PRINT USING is
doing. The other half involves an
automatic TAB f motion .

FEATURES OF PRINT USING:

The format in line 10 allows the
printing of 10 characters maximum *
(more or less may be used). *

Tte decimal point is
automatically inserted into the 3rd
to the last position

- If the number in question exceeds
999*99# a comma is automatically
inserted into the 7th to the last
position*

- If there is no number in the last
position ex in the last and second
to last positions# zeroes are
autoratieally inserted*

If there are more than 2 numbers
to the right of the decimal point#
the overage is automatically
truncated (chopped off).

ftost important for automatic
TABing, if the total aroint of
spaces needed by the formatted
number is less than 10# the PRINT
USING command automatically precedes
the formatted number with an aroint
of blank spaces equal to the
difference between 10 and the anoint
of characters of the formatted
number*

The TKS-BO# as it stands# only
allows 6 digits of accuracy as
compared to the 8 digit accuracy of
the Sinclair machine. The TRS-80 has
the potential for 16 digit accuracy
with added canmands which we won't
discuss here.

If we were allowed to use the
PRINT USING command on the Sinclair
Computer, we could add a line to the
program;

25 PRINT TAB 22;"";

and all the numbers printed on
the screen would have their decimal
points lined up in the 30th column
and would appear in a nice neat
vertical row.

What a shame that this command
does not exist for the Sinclair
machines*

I see the gentleman in the rear
has a tear in his eye. Don't fret.
It can still be done - it just
requires more work. Don't feel bad,
even owners of much more expensive

have to use the same kind of
techniques I am about to shew you,

Let us take these problems one by
one and try to overcome them.

First of all# because we are by
nature basically lazy# let us create
a routine that will allow the
generation of random numbers so that
we don't have to keep entering them.
ENTER the following program and RUN
it:

10 DIM A(10 )

100 FOR N=1 TO 10
110 LET A(N >*1000000 *

<RND*RND*RND>

120 IF A(NK. 00000001
THEN GOTO 110
140 PRINT N#A£N )

150 NEXT N

You will observe on the screen 10
random numbers that can be of any
amount of digits qp to eight and
have the decimal point at any
possible position. We will new have
these numeric values changed into
string variables by changing the
following lines:

10 D IM A$ ( 10 # 10 )

110 I ET A$<N)^Sm$ (1000000 *
RND*RND* RND*RND >

120 IF VAL A$ (NX, 0000000 1
THEN GOTO 110

130 IF ra©<. 5 THEN LET A$(N>*

A$(N# TO 5)+" 5 blank spaces "
135 IF THEN LET

A$(N ,6)=STR$ (I+(9* INT
RND ) )

140 PRIOT N#A$(N)

If this conversion is made, the
results would appear the same on the
screen as if the first program were
RUN except that we now get a wider
range of differences in the amount
of digits after the decimal point
and the amount of digits in the
number Itself.

A big difference has occurred#
however . These numbers have been
converted to string variables by the
STR$ function and because of this,
each number can now be formatted.

We will new trincate each number

to the maximim of 2 positions past
the decimal point. Add the following
lines to the existing program;

160 INPUT

170 PRINT AT 0,0;""?

200 POR N=1 DO 10
210 Q0SU8 1000
220 NEXT n
230 STOP

1000 LET A*=VAL A$(N)

1010 IET A=INT (100*A+.05)A00
1020 LET A${N>*STR$ A
1030 PRINT A$(N>

1040 RETURN

RUfl the program again and after
the first set of numbers is
displayed , press the ENTER key. You
will notice that the second set of
numbers will have no more than 2
digits after the decimal point. You
will also notice that each nonber is
put to the left of its old
correspond ing number so that you can
easily compare them.

We new have to add any trailing
zeroes that are necessary. The

follcwing routine will not only do
this but will line ip the numbers
with right margin justification and
will even add the separating oentnas
when necessary.

Add or change the follcwing

lines:

2120 PRINT TAB 16;A$<N)

2130 RETURN

This 2000 subroutine performs the
bulk of the formatting. The
breakdown of the entire program is
as follows ;

- Lines 10 to 150 create randan
numbers up to eight digits ..long ,

Line 110 creates the numbers and
line 120 checks to see if the number
is too small and if it is, goes bade
and gets another number.

Lines 130 and 135 are designed to
produce a greater amount of numbers
with one digit after the decimal
point for this exaaple, and line 140
prints each number.

This routine could be replaced by
your own such as a data input
routine or a routine that created
numeric data from other data. The
numeric data would then have to be
converted to string variables using
the STR$ function as outlined in
line 110,

Let us say that the
dimens ional i zed numeric var iable
A(N) was used in your program. Line
110 would then read:

110 LET A$(N»^STR$ ACN)

230 INPUT B$

240 PRINT AT 0,0;

300 FOR N = I TO 10
310 GQSUB 2000
320 NEXT N
330 STOP

2000 FDR 1=10 TO 1 STEP “1
2010 IF A$(N,IK>" " THEN
GOTO 2025
2020 NEXT I

2025 LET C$**A$(N,1 TO I)

2030 IF C$(I£N THEN

GOTO 2100 JL
2040 IF C$(IEN THEN

GOTO 2060

2050 LET CS=C$+",0"

2060 LET C$=C$+"Q"

2100 LET A$(N)=" 10 blank spaces w
2105 IF LEN C$>6 THEN LET C$ =

C$(l TO LEN C$-6)+ w ,*+C$(I£N
C$-5 TO LEN C$»

2110 LET A$(N,U-I£N C$ TO 10)=C$

“ Lines 160 to 220 and including the
subroutine starting with line 1000
tnxicate the numbers to include no
more than 2 digits past the decimal
point.

Line 170 sets up the starting

position for the first printed

number fran line 1030,

Subroutine 1000 converts the
String variable into a mmerie

variable in line 1000, truncates the
number in line 1010, and then
re-oonverts it back into a string
variable and prints it with lines

1020 and 1030.

- Lines 230 to 320 and including the
subroutine starting at line 2000
format the finished numbers through 1

string manipulation . i

'

Line 240 sets the format for the
starting position of the first
printed number fran line 2120.

The original string variables
are set to 10 blank spaces.
This is accomplished by the first
line in the progr^n, line number 10.
Tie STK$ function in line 110 studc
a randan number with a randan amount
of digits into each of these string
variables with the first digit being
in the first character position.

This means that most of the time,
sane of the right character
positions of the string variable
were left blank.

For our formatted numbers , we
need to accomplish three more
objectives ;

1 - to shift the total number in the
string so that the last digit is the
last character in the string

2 - to add trailing zeroes when
neccessary

3 - to insert a comma when the
number exceeds 999.99

The first objective is achieved
between lines 2000 to 2025 where a
na«r string variable (C$) is created.
Because it is not dimensional! zed,
<C$> cannot have any blank spaces on
either side of it and therefore can
easily have trailing zeroes and a
decimal point tacked on if
necessary.

<C$> is created by searching
<A$CN>> fran the right-most position
and going to the left until no more
blank spaces are encountered. <C$>
is then made to be equal to just
that part of <A$(N)> that has no
blank spaces.

Lines 2030 to 2060 add the
decimal .point and trailing zeroes by
searching <C$> bo see if it needs
any of them.

Since we now have <C$> almost in
the format we need it in, we have to
do something before we can re- insert
it back into <A$ CtO > and that is
that we have to clean out <A$(N» so
that it isn f t cluttered fc ip with any

part of the old numbers in the wrong
positions. This is done by line 2100
that sets it to be equal to 10 blank
spaces.

By the way, does any one know why
we chose 10 spaces to be the maximum
amount in our sample program? Yes,
the gentlenan in the back has his
hand up? I can hardly wait to hear
his answer.

Haven't learned much fran last
year, have you? As usual, his answer
is wrong. He said it is because the
program was written by a human, and
humans invented the decimal system
which has a base of ben because rtan
has ten fingers.

what that has to do with anything
we're talking about here. I'll never
know.

tic - the answer is - the 2X/TS
computers have a maximun of 8 digits
of accuracy for any number that is
manipulated through normal
mathematical procedures. Well when
we convert it to a string and add a
decimal point and a oatma, we now
have 10 total characters in the
formatted number.

Anyway, getting back to What we
were talking about, all that remains
for us to do now before re-inserting
<C$> back into <A$(fJ>>, is to insert
commas into the numbers that exceed
999.99, This is acccmplished by line
2105 which checks to see if <C$> is
more than 6 characters in length and
if it is, inserts the caima in the
proper place.

we now come to the final
operation before printing the number
and that is to re-insert <C$> into
<A$(N)>. You will renanber that when
<A$(fO> originally held a number,
the first digit was in the first
character position of the string. We
must have the exact qpposite occur
when we re- insert it and that is to
have the last digit, even if it is a
<0> occupy the last character
position of the string.

In other , words , originally the
blank spaces were after the number

1 1

cont, oi page 18

CASSETTES

PROGRAM

ISSUE

ALIEN-BASE/lK

JUN

ARTIST/lK

AUG

BAR-GEM A 6K

AUG

BASBCONA6K

APR

BIORHYTHdAEK

APR

BIRTHDAY AK

OCT

BOUNCING-BCMBS

APR

BULLETINA6K

ajjg/gct/dec

CHAINS AW/2K

DEC

CHAR-CODEAK

AUG

CIPHERA6K

JUN

CLOCKAK

JDK

FILEA6K

OCT

FRENZY /2K

DEC

instringak

APR

I NVQJTORY A6K

DEC

labyrinthAk

AUG

marquee-iak

JUN

MARQUEE- 2/16K

JUN

MESSAGEAK

AUG

MICRO-PROA K

ocr

MILEAGE/2K

DBC

MINEFIELD- 1/lK

APR

MINEFIELD- 2/IK

APR

MINI-PROA6K

OCT

MORTGAGE- 1/1 K

JIN

MORTGAGE - 2/1 6K

JUN

MULTIPLYAK

AUG

NAME/ ADD A 6K

AUG

NWESORTAK

APR

QUOTEA6K

DEC

RALLY AK

APR

reactionask

OCT

RIP-CFF/2K

OCT

RORSCHACHAK

APR

SCHAMBLQD-WORDS

JUN

SEAS. GREET. /2K

DBC

spider-danAk

APR

STAR-IANDERA6K

AUG

SYNCHRO-SMASH

OCT

twodatesAk

APR

DESCRIPTION

GAME

SPECIAL EFFECTS
BUSINESS
CTXMPOTER MATH
PERSONAL
PERSONAL
ARCADE GAME/1 6K
BULLETIN BOARD
ARCADE GAME
UTILITY

OODE/DECCDE WORDS
UTILITY

NAME/ADDRESS FILE

GAME

UTILITY

BUSINESS

ARCADE GAME

SPECIAL EFF EC T S

BULLETIN BOARD

SPECIAL EFFECTS

WORD PROCESSOR

VEHICLE MILEAGE ANAItfSIS

GAME

GAME

WORD PROCESSOR
ROME FINANCE
ROME FINANCE
EDUCATIONAL MATH
NAME/ADDRESS FILE
UTILITY
BUSINESS
GAME

SELF-TEST
SPECIAL EFFECTS
CRAPHICS DISPLAY
EDUCATIONAL GAME/1 6K
(KAPHICS DISPLAY
GAME

ARCADE GAME
ARCADE GAME/2K
UTILITY

1 2

ARTICLES IN THE 1982 ISSUES Of SYNCHRO-SETTE

THE COMPUTER TUTOR

ISSUE/pg

TITLE

DESCRIPTION

APR/6

READ, DATA & RESTORE

Simulating these caimands
in Sinclair BASIC

MfiY/6

DU>MY SCREEN MEMORY MAP

Manory map in BASIC

JLW/9

VARIABLE CONVERSION

Converting string variables t
and back again

JUI/9

WORD PROCESSING

Routines in BASIC

AUG/14

SYNTPOnC SUM

Checking to see if you typed
a program correctly

SEP/9

MCWTNG GRAPHICS

Routines in BASIC

OCT/8

SORT ROUTINES

Routines in BASIC

NOV/10

STRING MANIPULATION

Routines in BASIC

DEC/12

(SAFES

Business screen graphing tec hi

OTHER ARTICLES

ISSUE/pg

ARTICLE

DESCRIPTION

MAY/4

ARTIFICIAL INTELLIGENCE

Sanple programs

JUI/14

CHECKBOOK

Balancing program

MAY/11

COLOR COMPUTER

Sinclair Spectrum netfs

JUN/14

COLOR COMPUTED

Sinclair Spectrum news

APR/11

PROGRAM BLITZ

Ranpaek problems

APR/12

CASSETTE RECORDING

Proper methods of SAVEing and

MAY/14

CASSETTE RECORDING

Proper methods of SAVEing and

JUI/3

CASSETTE RECORDING

Proper methods of SAVEing and

NOV/7

CHESS

2X Master vs, Sargon

JUN/11

CIPHER MACHINE

Coding & Decoding messages

NCW/20

DATES

Utility progran

NOV/20

HAPPY HOLIDAYS

Graphics program

novai

HISTORY

First lady of computers

DEC/8

HISTORY

Birth of the modem computer

N0VA6

HOME BUDGET

Software revia*

JUIA1

IMPACT

Sinclair's market impact

ALGA

INFLATION

Oast calculating program

DECA6

PRINTER REVIEW

Sinclair & Mindware

AUGA

PYRAMID

Graphics program

APR A 4

SUPPORTING COMPANIES

Aftermarket products

JULA4

TITLE

Graphics program

4PR/1S

USERS' (SOUPS

elite & associations

«Y/15

USERS' QOJFS

Clubs & associations

nuAs

USERS' GROUPS

Clubs & Associations

5CT/13

VU-CALC

Software review

IAYA3

ZX-80 VS ZX-91

Comparisons

Other product anouncements and reviews are too numerous to list but appear in
he Editor Ronb lings oolurm.

1 3

Ever wonder how a sort routine
works? Is it hard for you to
visualize the swapping of
variables?

Here is a program that not only
allows you to see the variables

120 I£T M=1
130 I£T 1=1
140 FOR N=1 TO l£N B$

150 IP B$(N)=" " THEM GOSUB 100

change places but also generates the
individual variables fran the DATA
variable in line 110, This simulates
the READ, DATA and RESTORE ccnmands
found cn other BASICS,

To speed up the string variable
generation, you might want to add
the lines:

10 FAST
165 SLOW

160 NEXT N

170 FDR 1*1 TO 19 STEP 2

180 LET JwJ+1 T X T 4 I

190 GGOSUB 2000

200 NEXT I

210 LET P=0

220 LET M=20

230 LET M=INT M/2

240 IF M=0 THEM GOTO 500

250 LET P=P+1

260 PRINT AT 10,20;"PASS NO.

To slow down the swapping, add
the following lines:

2005 FOR C=1 TO 50

2006 NEXT C

2015 FOR 0=1 TO 50

2016 NEXT C

Try to locate both of the words
that are being swapped as they
change places on the screen. Line
310 checks to see if one of the
variables is larger than the other.
It does this by examining the
numeric value of the codes of each
of the characters in the variable.

270 FOR T»1 TO M
280 LET I=T
290 LET J=T+M
300 LET W=0

310 IF A$(IKA$(J) THIN GOTO 37

0

320 LET W=1
330 LET C$*A$(I>

340 LET A$(I)=A$(J)

350 LET A$<J)X:$

360 GOSUB 2000

370 LET I-J

380 LET J=J+M

390 IF J<21 THEM GOTO 310

400 IF W=0 THEM GOTO 420

410 GOTO 280

420 NEXT T

430 GOTO 230

If the first variable is larger
than the second, then lines 330, 340
and 350 swap them around.

100 DIM A$(20 ,11)

110 LET B$=" WATERMELON , BW JCXE
, TARANTUIA, KNEE-HIGH , FOOTBALL, SH
OE , STIIWER , CISTERN , POKER , KITE ,SL
OP , EYEBALL, LOCXJAW, FLUORESCENT, 2
EBRA, BUFFALO, INTEGER , NORMANDY , AU
TOMOBILE.JUKTSU,"

8 LET M=1
LET 1*1

FOR N=1 TO LEM BS
'IF B${N)*",» THEN GOSUB 100

500 PRINT AT 21,10; "SORT DONE :

, ■ ft

510 GOTO 510

1000 LET A$(I)=B$(M TO N-l)

1010 LET M=4)+l
1030 LET I-I+l
1040 RETURN
2000 LET D$*"

2010 PRINT AT I,0;A$( I) ;D$

2020 PRINT AT J,0;A$(J);D$

2030 RETURN

1 4

SYNCHRG-SETTE PRINTED
WITH DAISY WHEEL PRINTER

It seems like cnly a little while
ago we started printing the magazine
with the CITOH PRO-WRITER dot matrix
printer. This issue is being printed
primarily with the Radio Shack Daisy
wheel 2 printer. This simulates
typewriter quality print as solid
font devices are struck by a
miniature hanrner against the ribbon
and paper. This is, as qpposed to
the dot matrix method of pins
striking the ribbon against the
paper.

We hope you like the results.

SPECTRUM MICRO-DRIVES NOT DISK

release their micro- floppy ( unless
they make the mistake of
over-par icing it), Hie micro-floppy
is SPECTRUM'S main f future feature 1
to entice people to buy NOW.
("There's a fool bom It may
never be released here. Besides, if
their '$80,00' floppy is of the sane
quality as their $100.00 printer, it
won't be worth spitting on I

Did I mention, I WON'T be buying
a SPECTRUM?"

Strong sentiment, but we shall
see. For the price, I don't think
the consumer is expecting an IBM PC
and fron other sources, I have heard
the Spectrum is quite a buy for the
money.

Consensus of opinion regarding
the Spectrum MicroDrives was that
they would store data on small
circular disks. This is not the case
according to a European source.

The storage media is actually a
closed-loop cassette tape with an
average response time of 3.5 seconds
~ slower than a floppy disk drive
but still much faster than the
cassette systems we are used to.
Apparently, not all potential
purchasers are happy with this
situation as evidenced by an exerpt
from a letter copy I received:

"With the recent price^cuts by
the 'real' micro mfrs., I don't
think the SPECTRUM has a snowball's
chance here. It will have even LESS
of a chance when the J^anese

The Wall Street Journal recently
had an article telling the following
about the Sinclair computers:

7 100,000 Spectrums have been sold
in Britain in 7 months including
50,000 in December.

- 750,000 ZX-Bls and TS-lOQOs were
sold in the U,S. last year.

- 16K Spectrums or TS-2G0Gs will
sell in the U.S. for around
$150 .00 .

- 4BK Spectrums or TS-200Qs will
sell in the U.S. for around
$ 200 . 00 .

Micro-Drives for the
SpectrujV'IS-2000 will sell for
between $55,00 to $70,00 each.

1 S

- a special connector or interface
will be needed for the Micro-Drive
system and will sell for around
$40 *00.

- Timex is expected to drop the
price of the TS-1000 to $79,00

- approximately 14,000 outlets
across the U.S. are now selling the
TS-1000 and software.

If past records are any
indication of the Spectruio/TS-2000
future sales here In the U.S., the
gentlenan who wrote the "poison pen
letter" will indeed learn a lesson
about marketing. I'm sure Uncle
Clive could care less if he "bought
a Spectrum"*

The exact date of the debut of
the Spectrum/TS-2000 equipment into
the U.S, is anybody’s guess at this
time* We think the computers will
cone sometime in April or May with
the Micro-Drives in July or August
of this year.

AMATEUR RADIO

Ton McCarthy is locking for
feedback frcm people who are
interested in using the TS/ZX
ocmpuhers with amateur radio
equipment * either for . RTTY or CW
work or for practical software such
as keeping a log book, teaching CW,
etc.

Tati admits to not being a
programming wiz yet but maybe with
some help fran the editor and
interested subscribers, he can write
seme software and articles to appear
in SYNCHRD-S ETTE *

If anyone likes this idea and
would like to see it get' underway ,
drop a letter to SYNCHRO-SETTE in
care of Ton McCarthy/N9DRE along
with Ideas or software to share- Ton
told me to be sure bo specify that
this is to be a non -prof it
endeavor*

EDUCATIONAL PROGRAMS

If you are interested in programs
that instruct in an entertaining
manner, 2-BIT SOFTWARE has a number
of packages designed to teach
children and adults alike in the
fundamental aspects of computer
awareness .

Their philosophy involves a
belief that computers can stretch
minds, young and old and rather than
using the computer as a passive
fact-finder for flash-card style
drills, they design programs that
are open-ended, can be changed by
the user and structured for implicit
learning rather than for a
schoolroom approach* Most require
only 2K of memory and sell for
9.95,

Subjects of mathematics ,

probability and theory are covered
that encourage analytical and
strategic thinking skills with the
expected end result being that the
user is more comfortable with the
computer.

For further information or
literature, contact;

2-BIT SOFTWARE
Bnerson & stern
Computer Associates
13674 Boquita Drive
Del Mar, CA, 92014
619-481-3242

* see end

PROGRAM OF THE .MONTH CUB

Or ig inal P rog rams , Phoen i x ,
Arizona has announced the
cormencement of business of;

The Original Program of the Month
Club* They offer a wide selection of
programs for the Timex/Sinclair 1000
and ZX-81 cn cassette tape. Included
are such eatagories as games,
education, family financial, etc.
Programs are $5,99 or less and every
sixth program is FREE.

They operate very much like many
of the 1 book of the month clubs 1 ,
with limited ongoing purchasing

1

requirements, N&r members get their
first five programs for cnly 99
cents.

For further information, write to:

Contact: G. Rtssell * Electronics
RD 1 @CK 539
Caitre Hall, PA, 16820
814-364-1325 eves. * see below

The Original Program
of the Month Club
3763 West Crocus Drive
Phoenix, AZ, 85023

They will respond to all inquiries
but would appreciate a SASE, * see
below

tfINKY BOARD 2

TSG MAILING LISTS

If you would like to purchase t
mailing list of Users’ Groins,
Software suppliers or Hardware
si^pliers along with TS/ZX owners f
contact:

TSG Enterprises
54 Richwood Place
Denville, NJ, 07034

Mr. Russell has done it again!
The WB-2 will now:

Filter 16K RAMpak noise when
SAVEing programs for clean, easy
LQADing cassettes.

If you would like to get on t
mailing list in any of these areas,
send them the needed information

* tell en Synchro-Sette sent you!

- DUPLICATE (direct copy) any IS r
ZX cassette tape including those
special non-LISTable, non-SAVEable
cassette, programs .

Set optimum tape volume
immediately and precisely with LED
indicator lights for any cassette
you wish to LOAD,

- Earphcne^eavesdrop as you K3AD or
DUPLICATE without manipulating cable
plugs and cassette volume control.

Filter electrical noise and
interference when lOADing and LOAD
those "diff icult"’ cassettes with
ease.

Save time by LDADing and
DUPLICATING cassettes

SIMULTANEOUSLY.

- Use LED monitors for tape head
realignment for those really

"difficult" cassettes.

The complete unit assembled and
tested is S24.-00 - kit is $18.00.
$1.00 for earphone, PA residents add
6 % , overseas must be in U . S .

currency and add $2.00 shipping
(Canada & Mexico no extra shipping
charges ) .

A new mortgage plan
is available to homeowner*
and buyer* that has low*
er effective interest rate*—
sometime* even in single
digits. The plan— called the
Fannie Mae" Mortgage So-
lution— it available on any
one- to four-family home
on which the existing mort-
gage ia owned by Fannie
Mae. the nickname of the
Federal National Mortgage
Association, which is the
largest single source of mort-
gage money in the country.
Under the plan, existing
FNMA loan* can be "traded
in** by a home owner or
buyer for a new Fannie Mae
loan.

The new Loan can be for
up to 95 percent of the ap-
praised current market value
of the home. A brochure
that tell* all about the
Fannie Mae Mortgage Solu-
tion is available free by
writing to; Federal National
Mortgage Association, Mort-
gage Solution* 3900 Wiscon-
sin Avenue, N W,. Waihing-
ton, D C, 20V 16.

1 -P

direction. It was unveiled in 1947,
was three times as Large and twelve
times as fast. It was turned wer to
the Dahlgren Proving Ground to solve
problems in ballistics of guided
missies and supersonic aerodynamics
for the U. S, Navy.

Science owes many of its advances
to the probisms and needs of war.
World War 1 saw many new chemical
developments and World War 2
accelerated the development of the
computer and atonic research,

- Marilyn Buza

LETTERS CENT,

computers but not for the Sinclair.
Even if one did exist, I'm not sure
that after the programs were merged,
the variables would still be
intact ,

If any readers out there are
aware of or have had any experience
in this area, please let us know -
Ed.

Does anyone have an old ZX-80
manual that they don't need? Please
let me knew and how much you want
for it (cash, trade for software,
etc.) - Ed,

TUTOR CENT.

in the string. Now we want the blank
spaces to be at the beginning of the
string and proceed the number . Line
2110 acconplishes this.

Line 2120 prints the final
formatted number with a TAB
command.

This program is easy on the eyes
and the 1000 and 2000 subroutines
should be useful for any program
that requires formatted numeric
output involving dollars and cents*

If you have a printer, add a
line, 21 25 the same as line 2120 but
with a LPRIWT cannand.

No homework this time, but
experiment with this program and its
routines in other programs.

CLASS DISMISSED!

Do you know presidents talk to the
couitry the way men talk to wonen?
Tfray say, "Trust me, go all the way
with me, and everything will be all
right." Nine months later you 1 re in
trouble.

- Maureen Murphy
on the "Tonight* shew

How To Help Your

Is your child '‘computer
literate?” It's a term that's
being used a lot these days
to describe a person's basic
understanding of computers
and programming. In a few
years, many people entering
the job market without this
knowledge may face closed
doors. Today, many parents
are helping their children to
understand and use comput-
ers by purchasing a personal
computer for the home.

What is a personal com-
puter? Both in the home
and in the classroom, a per-
sonal computer is a tool for
managing and organizing in-
formation, as well as a
multi-purpose problem solv-
er. Small in size but big in
the amount of information
they can store, personal
computers are making it
possible for grade schoolers
to work, for example, with
geometry concepts years
earlier than usual.

Child With School

As an at-home tutor, a
personal computer teaches
youngsters languages, read-
ing* spelling and math skills*
as well as entertaining them
with game programs.

A computer should not
be intimidating to you or
your family. The Timex
Sinclair 1000 offers encour-
agement, and has been
called very “user friendly.”
Convenient and lightweight,
it can be used with any TV
set as a monitor.

Computers need software
to tell them what to do. Or,
you can quickly learn to
create your own programs.

A computer for children
should be compatible with
easy-to-use education pro-
grams. The TS1000 has soft-
ware packages specifically
designed for educational
use, but, importantly, its
instruction manual makes it
easy to learn basic pro-
gramming skills.

It's an important helper
for adults as well. A per-
sonal computer can help
you compute tax informa-
tion, assess your home ener-
gy output, balance your bud-
get, maintain recipe files or
catalog possessions. Through
the use of a modem, or com-
munications interface device,
for low additional cost, the
personal computer can give
authorized individuals ac-
cess to large data banks
containing financial infor-
mation, newswires and spe-
cific and general research
information.

As an at-home tutor,
a personal computer can
teach youngsters language,
reading, spelling and math-
ematical skills, as well as en-
tertain them with game
programs. It's also excel*
lent for drilling children in
fundamentals.

It's important to look for
certain features when choos-
ing a personal computer. Per-
sonal computers are fun, but
not toys. You should look
for the system that best suits
your needs and your bud-
get. One new computer, the
Timex Sinclair 1000, is only
$99.95. The computer has
2K internal memory, and a
1BK RAM pack is available
for a suggested retail price
of $49.95, The computer
also comes with a 90
day limited warranty from
Timex, another important*
1 consideration.

for t. hi ♦

g-BIT

SOFTWARE

' I' 3 J. n c 1 sir

CAMFS SAMPLER
r-| INF) VR * MACHINE
1 different qanes on each cassette

F t oft

Efterson ft Stern Associates

1367^ Etooiiita Drive

Del her, California 9701*

Send for 'jour FRE E catalog '

AHAL0C INTKlfACE t TAPI SIGNAL CORD I T I OKI I

{for the tiwi/IUelaLr computer)

VOTER in a complete package cMliltiflf of hardware and software that enable • your computer
to measure, diipliy and record "real world” analog signal*. Your computer can monitor anjr
physical phenomenon { pressure , Lithe, temperature, etc.) that can be represented by a DC
*0 L t age i A probe ia provided for air and Liquid temperature measurement ■ .

Your computer become* a "emift* digital voltmeter and thermometer with storage capability.
Ju*t chink of tha possible applicat ions . Use VflTIK and your computer to monitor the
temperature in a hone energy conservation project to **v* money and possibly qualify for
an energy ta* credit.

VOTEH * l*o amp 1 if ice and cleana up the tape signal for reliable LOADS * The tepe signet
conditioner circuit will allow you to LOAD tepe* with a Lower volume Betting on your tape
recorder , resulting in lea a noise and more dependable LOAD*. You will be able to LOAD
from t*pe* which would previously not comply.

VOTER requires no modification! to your computer and does not u*e the computer's expansion
connector, Leaving it free for other add-one such e* the memory pack and printer.

At only $59 <95 (assembled and tested), VOTER La the world' e moat coat effective analog
interface- for *n even better bargain the VOTER kit ie only $39.95. {Acquire* soldering
and appx 7 hr*.) VOTER come* with a detailed 35-page manual. Th* manual may be purchased
aeperately for $5 pp and applied to first purchase of a VOTER unit* If you ate not
satisfied with VOTER return within 15 day* for full refund. (Doe* not apply to kite.)
Send check or money order plus $1 for shipping and handling.

Down East Computers

P.O. BOX 3096 Greenville, NX. 27834

(919) 752-7817 eves.

20